TOPIC:

ID Code: K2-29
Purpose: Demonstrate that the sign of the induced voltage depends on the direction of the field as well as whether the field is increasing or decreasing in magnitude.
Description: Two versions of this demonstration, shown in the photograph above, will be delivered. Each consists of red and green LEDs, which respond to the two possible directions for the induced voltage, connected across a coil. When the magnetic flux through the coil is rapidly changed, one of the two LEDs activates, depending on the direction of the flux change. The flux through the coil at the left is changed by making or breaking the magnetic circuit; for the setup at the right the flux change is created by passing the magnet rapidly through the coil. An interesting effect can be obtained by dropping the magnet through the coil.
Availability: Available